Chlorine stable powder gelling composition

ABSTRACT

The disclosed invention is for a gelling composition which when added to water forms a gel useful for stabilizing a chlorine release additive. A significant advantage of this invention is the increased chlorine stability and hence increased available chlorine for cleaning and sanitizing during contact of the gel and a solid surface. The gelling composition consists essentially of (A) an anionic heteropolysaccharide biopolymer gelling agent, (B) a neutral diluent selected from the group consisting of Na2SO4 and NaCl, (C) a linear alkyl benzene sulfonate wherein the alkyl group includes from 12 to 14 carbon atoms, (D) propylene glycol liquid dispersing agent, and (E) fluorescein dye.

I United States Patent 1151 3,666,679

Crotty et al. 1 May 30, 1972 1 1 CHLORINE STABLE POWDER 1 ReferencesCited GELLING COMPOSITION UNITED STATES PATENTS 1 Inventors: Homer y;Charles Coffey, both 2,550,622 4/1951 Taub ..252/316 x of Cincinnati;Thomas Tesdflhl, re 3,028,338 4/ 1962 Parker, Jr. ...252/30l.2 P all OfOhlO 3,383,307 5/1968 Goetz ..252/3 16 3 238141 3/1966 Gatza .252/316 73A Ch ed C I: l 1 cmcmna Ohm 2,447,475 8/1948 Kaberg et a] ..252/355 x[22] Filed: Apr. 23, 1970 Primary Examiner--Richard D. Lovering [21]APP]: 31,373 AttorneyEugene M. Bond 7 Related US. Application Data 57 1ABSTRACT [63] commuanon'm'pan of The disclosed invention is for agelling composition which 1968e when added to water forms a gel usefulfor stabilizing a chlorine release additive. A significant advantage ofthis in- [52] U.S. Cl ..252/3l6, 134/4, 252/79. 1 vention i th i r a dchlorine stability and hence increased 2 2/ 2 l available chlorine forcleaning and sanitizing during contact of 252/144, 252/ 154, 252/ 164,252/165, 252/187, the gel and a solid surface. The gelling compositionconsists 252/353, 252/354, 252/355, 252/539, 252/545, essentially of (A)an anionic heteropolysaccharide 252/DlG. l biopolymer gelling agent, (B)a neutral diluent selected from [51] Int. Cl. ..B0lj 13/00 the groupconsisting of Nat- 50 and NaCl, (C) a linear alkyl [58] Field of Search..252/316, 164, 353, 301.2 R benzene sulfonate wherein the alkyl groupincludes from 12 w 14 carbon atoms, (D) propylene glycol liquiddispersing agent, and (E) fluorescein dye.

2 Claims, No Drawings CHLORINE STABLE POWDER GELLING COMPOSITION Thisapplication for United States Letters Patent is a continuation-in-partof application Ser. No. 749,585 filed Aug. 2, 1968 and now U.S. Pat. No.3,578,499.

The present invention relates to a gelling agent which when added towater forms a gel useful for stabilizing a chlorine release additive.More particularly, the present invention provides an improved chlorinestable gel, and a method for cleaning or sanitizing a variety ofirregularly shaped surfaces by permitting a surface adhering layer ofsaid gel to remain in place for a period of time sufficient for cleaningand sanitizing, after which the gel is removed by rinsing. After removalof a surface adhering film of applied chlorine-containing gelcomposition, a clean-sanitized surface remains.

Numerous cleaning and sanitizing compositions are available to the art.Typically, these compositions appear in concentrated form for additionto a solvent such as water which may be then applied to a surface to becleaned. Incidental to cleaning, these compositions may includegermicidal agents or related materials for sanitizing a surface beingcleaned. A defect in conventional compositions used heretofore has beenthe high fluidity characteristic which upon application to, for example,vertical surfaces, results in the applied materials having a tendency torun and ineffectively clean the surface. Resultingly, in most instances,insubstantial contact time is permitted for adequate cleaning andsanitizing of surfaces to be cleaned.

Considerable interest in polysaccharides produced by the bacterialfermentation of carbohydrates has has been exhibited in recent years.These polysaccharides, having properties which permit their use asthickening agents for water, have been used as foam enhancers for beer,as emulsion stabilizers for mayonnaise and the like, and as waterthickening agents for use in secondary recovery operations carried outin the petroleum industry.

It has been known, as described in U.S. Pat. No. 3,383,307 that is ispossible to make gels by adding a polysaccharide produced fromcarbohydrates by the action of bacteria of the genus Xanthomonas, towater at rather low levels such as from 0.05 to 5 weight percent basedon the weight of water. into this thickened water is added a salt of atrivalent metal such as aluminum sulfate and, if desired, a metallicpromoter such as powdered zinc metal. The addition of a trivalent metalsalt such as aluminum sulfate and a metallic promoter such as powderedzinc, to the polysaccharide-thickened water, results in gel formation.

It has now been found by practice of the present invention, thatchlorine stability of a chlorine release additive is improved by using aparticular polysaccharide-thickened water system. Appropriate additivesfor cleaning and sanitizing may be included as desired with the presentgel which is applied as an adhering gel film to a surface to be cleanedand sanitized for a period of time affording adequate cleaning andsanitizing of the surface. Thereafter, the applied gel may be readilyremoved by rinsing with water.

Generally stated, the present invention provides a chlorine stablegelling composition including a particular gelling agent identified asanionic heteropolysaccharide characterized with high dilute solutionviscosity, and if desired a neutral diluent, a wetting agent, adispersing agent, and a dye or coloring additive. Upon addition inprescribed amounts to a suitable solvent such as water, the gellingcomposition forms a thixotropic or gelled mass which when appropriateadditives including an available chlorine containing additive areintroduced for cleaning or sanitizing may be readily applied as a thinadhering film of gel solution cleaner to a surface for cleaning andsanitizing thereof. The thin film is permitted to adhere to the surfacefor a period of time sufficient to provide effective cleaning andsanitizing after which period the thin film is removed by rinsing withwater.

The present invention also provides a method for cleaning and sanitizingsurfaces and particularly irregularly positioned wall or equipmentsurfaces disposed either overhead or vertical with reduced tendency forspillage and running of the cleaning composition as is typicallyencountered when using conventional solutions or detergent compositions.

The various components of the chlorine stable composition, whenformulated, may be used for general cleaning when employed in a watersolvent system although other less conventional solvents may be employedprovided the necessary thixotropic or gel surface adheringcharacteristics are obtained in the composition applied to a surface tobe sanitized or cleaned.

The gelling agent typically employed as a component of the presentcomposition is generally one characterized with heat stability, pHstability, high shear stability, and high dilute solution viscosity.Such gelling agents are exemplified by those water/soluble anionicheteropolysaccharide biopolymers having sufficiently high molecularweight such that dilute solutions thereof, such as. .1 ,percent watersolutions, may be characterized with a Brookfield Model LVF Viscometersolution viscosity from about L500 to 5,000 centipoises at 25C andpreferably form about 2,500 to about 3,500 centipoises at 25C. Such highmolecular weight biopolymers are generally found to show improvedresistance to chlorine attack over related low molecular weight polymershaving lower dilute solution viscosity. A particular gelling agent founduseful herein is polysaccharide type materials such as anionicheteropolysaccharide thickening agent manufactured by General Mills,Minneapolis, Minnesota under the name Biopolymer XB-23." This materialis supplied as a minus mesh tan powder having a 1 percent water solutionviscosity of from about 2,000 to about 4,000 centipoises, and preferablyabout 2,500 to about 3,500 centipoises at 25C when measured with aBrookfield Model LVF Viscometer.

Other related water soluble materials may be employed such as thoseanionic heteropolysaccharide biopolymeric materials derived by microbialfermentation, and the like. Typically, these materials are water solublewhile providing heat stability, pH stability, and high shear stabilitywhile retaining the ability to form a chlorine stable thixotropic orgelled mass when added to a suitable solvent such as water or the like.Those related materials having high molecular weight and hence highdilute solution viscosity and improved resistance to chlorine attack aregenerally preferred due to greater effectiveness herein.

Powder gelling compositions including the high dilute solution viscositygelling agents described herein are found to provide longer lastingsurface adherence properties to the present thixotropic mass or gelprepared therefrom using a chlorine release additive as a component ofthe gel. Moreover high dilute solution viscosity gelling agents impartgreater retention of available chlorine to the present gel than isobserved when a related gel is prepared using similar gelling agentsexcept having lower dilute solution viscosity.

Generally, wide ranges of gelling agent may be included in formulatingthe present chlorine stable powder gelling composition which may appearas a concentrated formulation. Typically, however, the gelling agent isincluded in an amount from about 20 to about 60 parts by weight althoughif desired the gelling agent may be included in an amount up to about100 parts by weight based on the weight of the powder gellingcomposition.

An optional component which may be included in the present chlorinestable powder gelling composition is a neutral diluent such as sodiumsulfate, sodium chloride, and the like which may be added in anysuitable amount up to parts by weight and typically in an amount fromabout 40 about 80 parts by weight based on the weight of the powdergelling composition. Various additional materials may be added asneutral diluents providing the materials characterize the presentcomposition with a substantially neutral pH in the range of about pH 6to about pH 8 while retaining the other desired properties of thecomposition while further retaining surface adhering properties of thethixotropic or gel cleaning solution derived from the powder gellingcomposition.

Another optional component which may be included in the present chlorinestable powder gelling composition is a wetting agent exemplified by alinear alkyl benzene sulfonate type material wherein the alkyl group mayinclude from about 12 to about 14 carbon atoms. The wetting agent, whereincluded, is desirably characterized as an anionic agent although it isrecognized that nonionic surfactants may also be employed. One wettingagent found useful herein is the commercially available sodium sulfonateof dodecylbenzene. Wetting agents may be included in an amount up toabout 10 parts by weight and preferably in an amount from about one toabout four parts by weight based on the weight of the powder gellingcomposition.

Yet another optional component which may be included in formulating thepresent chlorine stable powder gelling composition is a liquiddispersing agent exemplified by propylene glycol or the like. Thedispersing agent is found useful in formation of a composition havingcomponents uniformily dispersed throughout. The dispersing agent may beadded in an amount up to about 10 parts by weight and desirably in anamount of about one to about three parts by weight based on the weightof the powder gelling composition.

A dye or coloring agent, although an optional component, is desirablyadded to the chlorine stable powder gelling composition to provide asuitable indicator for application and removal of a thin film or surfaceadhering gel. The amount of dye or coloring agent which is added information of the present composition is that sufficient to form asuitable indicating means by color contrast to effectively indicate thepresence of a thin film of cleaning gel applied to a surface to becleaned. Typically, a suitable dye found useful herein is fluoresceinwhich may be added in an amount up to about one part by weight andpreferably in an amount of about 0.1 to about 0.3 part by weight to thecomposition.

Although not required in the present composition, it is recognized thatadditional components such as filler materials, antiseptic materials,sanitizing materials, and the like may be usefully added provided thesematerials do not deleteriously affect formation of a thixotropic orgelled mass when the powder gelling composition is added to a suitablesolvent such as water.

The various components used to formulate the present chlorine stablegelling composition may be combined by uniformly mixing the variouscomponents until a substantially uniform blend is obtained.

The present chlorine-stable powder gelling composition may be used toform an effective gel or gel solution cleaner of which the gellingcomposition forms a component. A second component included in thepresent gel solution cleaner is a chlorine release additive such aschlorinated trisodium phosphate, chlorinated isocyanurates, sodiumhypochlorite, and the like. A third component included in the presentgel solution cleaner is a solvent, principally water for reasons ofeconomy although other suitable solvents may be employed provided thenecessary gel and chlorine stability factors are not significantlyaltered.

A concentrate or blend of chlorine stable powder gelling composition maybe added to a suitable solvent such as water or the like for formationof a chlorine stable thixotropic mass or gel. The concentrated orblended powder gelling composition may be added in an amount up to about10 percent by weight and desirably in an amount from about 0.1 percentup to about percent by weight based on the total weight of water.Preferably, the powder gelling composition is added in an amount fromabout 0.5 percent up to about 3 percent by weight based on the totalweight of water desirably at a temperature of about 180F. to form auseful surface adhering film when applied as a thixotropic mass.

Thereafter, the gel solution is desirably cooled prior to dis solvingthe chlorine release component therein although the chlorine releaseadditive may be added to the gel at the gel solution preparationtemperature if desired. The temperature to which the gel is cooled foraddition of the chlorine release component is preferably the temperatureat which the gel cleaner solution is to be used for cleaning andsanitizing. In many applications a useful temperature therefor is in arange from about to about 70F. A typical use temperature is roomtemperature (i.e., about 70F).

The chlorine release component may be added in an amount such that fromabout 200 X 10' to about 10,000 X 10' part by weight of availablechlorine is added, and preferably from about 200 X 10 to about 2,000 X10 part, based on one part by weight of water.

The gel solution cleaner may be formed by uniformly mixing the variouscomponents thereof until a substantially uniform mixture is obtained.

Various additional materials may be added to the thixotropic mass suchas for example, acidic or alkaline materials for cleaning and sanitizingpurposes, as well as disinfectant materials all having water solubleproperties. These materials are added in any effective amount asdesired. Various other materials such as deodorizing agents and the likemay be included in the thixotropic mass if desired. Examples ofsanitizing agents customarily'employed in related compositions and founduseful herein include chlorinated phenyl derivatives and the like aswell as related halogen substituted phenol derivatives and halogenseither elemental or complexed.

After the thixotropic mass or gel has been prepared with agents forcleaning and sanitizing, the gel is available for application to asurface which is to be cleaned or sanitized. Application of thethixotropic mass may be by brushing or spraying although any suitablemeans such as roll application or the like may be employed. Afterapplication of a surface adhering gel to a surface to be cleaned andsanitized, the film of gel is permitted to adhere to the surface for adesired period of time sufficient to provide adequate and effectivecleaning and sanitizing actions. It is typically found that a film ofgel may be applied and retained in position for a period of time suchas, for example, about 30 to about 60 minutes, although shorter orlonger periods may be provided depending upon the strength of theparticular components of gel and the degree of cleaning and sanitizingrequired.

After the cleaning and sanitizing period, the thin film of gel may beremoved by any suitable means. A desirable method for removing theapplied film is by application of water which may be either sprayed orbrushed over the surface of the applied film. Various other means may beused to destroy the film of surface adhering gel for removal of the filmfrom the surface to which it is applied. For example, the gel may bebroken or destroyed by addition of strongly alkaline materials such as astrong solution of sodium hydroxide having a pH of about 12.

It is generally found that after application of the present gel film andremoval thereof from a surface, the surface is effectively sanitized andsubstantially cleaned.

In order to further illustrate the present invention, the followingexamples are given wherein all parts are by weight unless otherwiseindicated:

EXAMPLE 1 A powder gelling composition is prepared by blending in amixer the following ingredients in the order and amount listed:

Ingredient Parts by weight Kelzan M. Gum-(Xanthomonas hydrophilic Twoparts by weight of this powder gelling composition prepared wasdissolved in 100 parts of F water to form a thick gel solution. To theresulting gel solution at lF was added chlorinated trisodium phosphatesufflcient to provide 600 ppm (parts per million) of available chlorine.After 1 hour the available chlorine content was found to be about 75ppm.

It is noted that while good stability of chlorine (i.e., time retentionof available chlorine) is observed for the gelled cleaner of Example lllusing Kelzan M as gelling agent. even better chlorine stability isobserved for the Example IV gelled cleaner using Biopolymer XB-23 asgelling agent. Two hun- EXAMPLE u dred or more ppm chlorine is observedto be available for a The procedure of Example I was repeated exceptKelzan longer perlod in the lnstance of Blopolymer X B-23 than for M wasreplaced by a corresponding amount of a lilzlalrll aMndulsrlg therelated gel cleaner formulatlons of Exampolysacihziride gelling i g ggsi as gg 10 p Similarly surface adhering properties of the Example IV2332; 5 :22; 0 is i d 532:5 gelled cleaner are observed to be evenlonger lasting than the Exam le Ill elled cleaner. This is attributed toincreased rehetemgolysacchande thickening agent prqduced by thefersistanse to Ehlorine attack for Biopolymer XB-23 having memanor. of acafl.)ohydrate by the ximmqmonas higher dilute solution viscosity (e.g.3 000 cp. for 1 percent campestrls and available from General Mills andldentlfied as Solution at C) and higher molecuiarsweight than Kelzan MBiopolymer XB-23" This gelling agent is described in detail (e 700 c for1 cent Solution at 25cc) in Canadian Journal of Chemistry, Vol. 40,pages 2066 et seq. 7 p and pages 2188 et seq., 1962, and in Vol. 42thereof, pages EXAMPLE v 1261 et seq., 1964. The material is reported tobe composed of D-glucose, D mannose, and D-glucuronic acid in the ratiofil f f gf P im?! by fj m a ofabout 2.8:3.0:2.0. To the resulting gelsolution at 100F was P e lems t e er added chlorinated trisodiumphosphate sufficient to provide hsted: 600 ppm. of available chlorine.After 1 hour the available chlorine content was found to be 264 ppm. Theresulting lngredlem Pans by weght warm alkaline gel solution was sprayedonto the metal meat processing equipment (conveyes, neoprene cuttingboards, Sodium Sulfate 56.85 band saws, stainless steel tables) in ameat processing plant fggggmi ggjg 40-00 cutting room area. The gel wasallowed to cling to the surfaces g oxide Adduct for about -40 minutes,then rinsed off with high pressure (100%) Cloud Point, 1%, warm water.The cleaning results were found to be excellent 30 P and the surfaceswere free of meat fat soil and gel cleaner. fgg zgg $5: l 5

EXAMPLE Ill Two parts by weight of Kelzam M Gum containing powdergelling composition prepared as in Example I was dissolved in EXAMPLE VI0 [00 of 180 water to form a thick i soluuon'.To the A powder gellingcomposition is prepared by blending in a resulting gel solutlon at roomtemperature(l.e.,approxlmately mixer the following in rediems in theorder and amounts 70F) was added an amount of chlorinated trisodiumlisted g phosphate sufficient to provide 600 ppm of available chlorine4O in the thus formed gelled cleaner-sanitizer. The amount of in rediemP Sb Wei ht available chlorine retained in the gel at various times overapg a y g proximately 3.5 hours was determined using standard titrationtesting therefor known in the art. Test results are shown in g ggg l fig333 Table A below. Sodium N-methyl. N-

Oleoyl Taurate 100%) 2.0 EXAMPLE IV Propylene Glycol l.0 Fluorescein Dye.15 Two parts by weight of Blopolymer XB-23 anlonlc heteropolysaccharidecontaining powder gelling composition prepared as in Example II wasdissolved in 100 parts of 180F water to form a thick gel solution. Tothe resulting gel solution EXAMPLE v at room temperature (i.e.,approximately 70F) was added an amount of chlorinated trisodiumphosphate sufficient to propowder gelllng g l p p by blendmg m a vide600 ppm of available chlorine in the thus formed gelled 9 the followmgmgredlems m the Order and amounts cleaner-sanitizer. The amount ofavailable chlorine retained in hsted: this gel at various times overapproximately 3.5 hours was determined using titration testing as inExample 11]. Test lngl'edlem Pans by wegm results for Examples Ill andIV are shown in Table A below.

Sodium Chloride 56.85 TABLE A Biopolymer XB-23 40.00

Sodium Linear Dodecyl Benzene Sulfonate 100%) 2.0 Ethylene Glycol 1.0Available Chlorine, ppm Fluorescein Dye 0.15

Ex. lV Gelled Time Since Gelled Ex. lll Gelled Cleaner (Bio- CleanerPrepared Cleaner (Kelzan polymer XB-23 minutes M Gelling Agent) GellingAgent) EXAMPLE VIII 0 600 600 A powder gelling composition is preparedby blending in a 10 451 602 mixer the following ingredients in the orderand amounts 40 339 414 listed, 70 225 300 100 188 300 220 57 151Ingredient Parts by weight Sodium Sulfate 56.85

Biopolymer XB-23 40.0 Sodium Linear Alkyl Napthalene Sulfonate 100%) 2.0Propylene Glycol 1.0 Fluorescein Dye l EXAMPLE IX Two parts by weight ofthe powder gelling composition prepared in Example V is dissolved in 100parts of l80F water to form a thick gel solution. Chlorinatedisocyanurate is dissolved in the gel solution at 70F in an amountsufficient to provide 2,000 ppm available chlorine. The resulting gelsolution is sprayed onto soiled metal and concrete surfaces in a meatplant smokehouse. The gel is allowed to cling to the soiled walls andceilings for about 20-30 minutes, then the surfaces are rinsed with warmwater to remove the gel and soil. The cleaning results are found to beexcellent and the surfaces are free of gel and soil.

EXAMPLE X Two parts by weight of the powder gelling composition preparedin Example Vl is dissolved in 100 parts of l80F water to form a thickgel solution. Chlorinated isocyanurate is dissolved in the gel solutionat 100F in an amount sufficient to provide 500 ppm available chlorine.The resulting warm gel solution is sprayed onto metal meat processing(conveyors, neoprene cutting boards, band saws, stainless steel tables)in a meat processing plant cutting room area. The gel is allowed tocling to the surfaces for about 30-40 minutes, then rinsed off with highpressure warm water. The cleaning results are found to be excellent andthe surfaces are free of meat fat soil and gel cleaner.

EXAMPLE Xl Two parts by weight of the powder gelling compositionprepared in Example Vll is dissolved in 90.parts of l80F water to form athick gel solution. Sodium hypochlorite is dissolved in the gel solutionat 70F in an amount sufficient to provide 600 ppm of available chlorine.The resulting gel solution is sprayed onto metal surfaces containingprotein, lime deposits, and metal oxides. After the gel solution hasclung to the metal surface for about -30 minutes, the surfaces arerinsed with warm water. The cleaning results are found to be excellentwith brightening of the metal, dissolving of the metal oxides, andsoftening and dissolving of the protein soil.

EXAMPLE XII Two parts by weight of the powder gelling compositionprepared in Example VIII is dissolved in parts of F water to form athick gel solution. Chlorinated trisodium phosphate is dissolved in thegel solution at 70F in an amount sufficient to provide 1,500 ppmavailable chlorine. The resulting alkaline gel solution is sprayed ontosoiled metal and concrete surfaces in a meat plant smoke house. The gelis allowed to cling to the soiled walls and ceilings for about 20-30minutes, then the surfaces are rinsed with warm water to remove the geland soil. The cleaning results are found to be excellent and thesurfaces are free of gel and soil.

It is understood that the foregoing detailed description is given merelyby way of illustration and that many variations may be made thereinwithout departing from the spirit and scope of this invention.

What is claimed is:

l. A chlorine stable powder gelling composition which consistsessentially of:

A. from about 20 to about 100 parts by weight of an anionicheteropolysaccharide biopolymer gelling agent having heat stability, pHstability, high shear stability, and l percent water solution viscosityof from about 2,000 to about 4,000 centipoises at 25C;

B. from about 40 to about 95 parts by weight of a neutral diluentselected from the group consisting of sodium sulfate and sodiumchloride;

C. from about one to about 10 parts by weight of a linear alkyl benzenesulfonate wherein the alkyl group includes from about 12 to about 14carbon atoms;

D. from about 1 to about 10 parts by weight of propylene glycol liquiddispersing agent; and

E. up to about 1 part by weight of fluorescein dye.

2. The chlorine stable powder gelling composition of claim 1 wherein A.the heteropolysaccharide gelling agent is present in an amount fromabout 20 to about 60 parts by weight,

B. the neutral diluent is present in an amount from about 40 to about 80parts by weight,

C. the linear alkyl benzene sulfonate is present in an amount from aboutone to about four parts by weight,

D. the dispersing agent is present in an amount from about one to aboutthree parts by weight, and

E. the dye is present in an amount from about 0.1 to about 0.3 part byweight.

2. The chlorine stable powder gelling composition of claim 1 wherein A.the heteropolysaccharide gelling agent is present in an amount fromabout 20 to about 60 parts by weight, B. the neutral diluent is presentin an amount from about 40 to about 80 parts by weight, C. the linearalkyl benzene sulfonate is present in an amount from about one to aboutfour parts by weight, D. the dispersing agent is present in an amountfrom about one to about three parts by weight, and E. the dye is presentin an amount from about 0.1 to about 0.3 part by weight.